Mechanical regulation of endocytosis by protein condensate capillary forces
Max Ferrin, Postdoctoral Researcher
Background and Motivation
Endocytosis internalizes membrane cargo into vesicles
(Kaksonen and Roux, 2018)
Endocytosis internalizes membrane cargo into vesicles
(Kaksonen and Roux, 2018)
How do capillary forces of a protein droplet influence endocytic membrane bending?
How do capillary forces of a protein droplet influence endocytic membrane bending?
How do capillary forces of a protein droplet influence endocytic membrane bending?
Modeling endocytosis with droplet
Geometrical model of endocytosis mechanical energy
Geometrical model of endocytosis mechanical energy
Geometrical model of endocytosis mechanical energy
Geometrical model of endocytosis mechanical energy
Geometrical model of endocytosis mechanical energy
Geometrical model of endocytosis mechanical energy
Geometrical model of endocytosis mechanical energy
Visualization of geometrical model reaction coordinate h
How does the droplet regulate invagination?
1: Droplet can provide net assistive force to endocytosis
1: Droplet can provide net assistive force to endocytosis
1: Droplet can provide net assistive force to endocytosis
2: Droplet drives late invagination to completion
2: Droplet drives late invagination to completion
2: Droplet drives late invagination to completion
3: Droplet produces early invagination energy barrier
3: Droplet produces early invagination energy barrier
3: Droplet produces early invagination energy barrier
3: Droplet produces early invagination energy barrier
4: Droplet volume controls energy barrier magnitude
4: Droplet volume controls energy barrier magnitude
4: Droplet volume controls energy barrier magnitude
4: Droplet volume controls energy barrier magnitude
Proposed mechanical role of condensate in endocytosis
Outlook
Validation of geometrical model results with continuum mechanics model
| Geometrical model | Continuum mechanics model |
 |
Endocytosis is qualitatively different from other examples of droplet-mediated membrane bending
(Kusumaatmaja et al., 2021; Lu et al., 2022)